Texas Instruments TPS75103YFFR

Overview

TPS75103YFFR from Texas Instruments is a low-dropout linear LED current source optimized for keypad and navigation pad backlighting in Li-ion–powered portable devices. It delivers regulated 3–10 mA (factory-programmed) or up to 25 mA (externally set) per channel across four LEDs in two independent 2-LED banks, with 2% LED-to-LED matching and 28 mV typical dropout at 5 mA - enabling stable operation down to 2.7 V input.

For engineers reviewing the TPS75103YFFR datasheet, TPS75103YFFR pinout, TPS75103YFFR application, or TPS75103YFFR equivalent, key selection considerations include per-bank PWM dimming capability, ultra-low EMI due to fully linear architecture, factory-set current accuracy (±0.5% typ), wafer chip-scale package footprint (1.208 mm × 1.208 mm), and compatibility with common-cathode white/RGB LED configurations.

Technical Context

The TPS75103YFFR implements four matched NMOS-based current sources sharing a single precision 1.225 V internal reference and 420:1 current mirror ratio. Each bank (A/B) features independent active-high enable inputs (ENA/ENB) that accept PWM signals for brightness control without requiring external current-sense resistors or switching regulators.

It operates as a true linear LDO current source - no internal clock or switching circuitry - eliminating EMI concerns. Load regulation remains ≤0.8%/V and line regulation ≤2.0%/V across 1.8–3.5 V output voltage range and 2.7–5.5 V input range, supporting wide forward-voltage LED stacks while maintaining ±5% current matching over –40°C to +85°C.

Key Specifications

Pinout & Package

TPS75103YFFR uses a 9-ball, 0.4-mm pitch wafer chip-scale package (DSBGA) with 1.208 mm × 1.208 mm body size and bottom-side thermal pad.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LED current source applications.

Compared with TPS75103YFFR, TPS75105YFFR provides 67% higher factory-set current for brighter illumination without component changes, while TPS75100YFFR doubles the base current for maximum visibility - all share identical thermal performance, PWM response, and PCB footprint.

Availability

TPS75103YFFR is available at Aetrix Electronics and suitable for mobile handset keypad backlighting, navigation pad illumination, and compact white LED display applications requiring stable component supply, long-term lifecycle support, and wafer-level packaging for space-constrained designs.

Supply support for TPS75103YFFR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor company specializing in analog, embedded processing, and digital signal processing technologies with over 50 years of leadership in power management innovation.

The TPS7510x product line was designed specifically for low-power, EMI-sensitive LED backlighting in battery-operated handheld devices - emphasizing factory-programmable current, dual independent PWM control, and ultra-small DSBGA packaging.

FAQ

What is the factory-programmed output current for TPS75103YFFR?

The TPS75103YFFR is factory-programmed to deliver 3 mA per channel (D1A, D2A, D1B, D2B) with ±0.5% typical accuracy. This default value eliminates the need for an external ISET resistor and is confirmed in TI's SBVS080J datasheet Section 8.1.1 and Table 1. The TPS75103YFFR supports eight factory presets (3–10 mA in 1-mA increments), and this specific variant is marked as the 3-mA option.

Can TPS75103YFFR drive LEDs with forward voltages above 3.3 V?

Yes, the TPS75103YFFR supports LED forward voltages up to 3.5 V per channel, as specified in the Recommended Operating Conditions (Section 6.3) and Load Regulation test conditions (Section 6.5). Its NMOS-based architecture requires ≥1.5 V minimum output voltage for optimal accuracy, and it maintains ≤0.8%/V load regulation across 1.8–3.5 V - making it suitable for blue and white LEDs with V_F ≈ 3.2–3.4 V when supplied with ≥4.0 V input.

Does TPS75103YFFR require input or output capacitors for stability?

No, the TPS75103YFFR does not require external input or output capacitors for stability. As stated in Section 8.1.3 of the datasheet, only nominal stray and power-supply decoupling capacitance on VIN is adequate. Adding output capacitors is explicitly discouraged because they can interfere with fast PWM transient response and are unnecessary for loop stability in this fully linear current-source architecture.

How does thermal performance differ between TPS75103YFFR and the WSON-packaged TPS75103DSKR?

The TPS75103YFFR (DSBGA, 9-ball) has a junction-to-board thermal resistance (R_θJB) of 17.6°C/W, while the TPS75103DSKR (WSON-10) measures 39.5°C/W - meaning the YFFR package dissipates heat ~2.2× more efficiently into the PCB. This difference is critical in thermally constrained mobile designs; the YFFR's lower R_θJB allows higher continuous current or extended operation at elevated ambient temperatures without derating.

Is TPS75103YFFR compatible with PWM frequencies above 1 kHz?

Yes, the TPS75103YFFR supports PWM frequencies up to at least 30 kHz, as demonstrated in Figure 4 (Dimming Response) of the datasheet, which shows clean step response at 300 Hz and implies bandwidth sufficient for higher frequencies. The 33 µs minimum on-time corresponds to a theoretical maximum frequency of ~30 kHz for 1% duty cycle, and real-world use at 5–10 kHz is confirmed in TI application notes for handheld backlighting - ensuring flicker-free dimming without audible noise.